Acid-resisting apparatus



Dec. E7, H929. G. D. KNIGHT ACID HESISTING APPARATUS Filed April 27 attentats atented Dec. 17, 1929 UNITED STATES PATENT OFFICE GEORGE D. KNIGHT, OF BEDWOOD CITY, GALIFOIlzl-NIA,l ASSIGNOR TOxEMOBY WIN SHIP, OF MACON, GEORGIA AGID-RESISTING APPARATUS Application led April 27,

The present invention relates to improvements in acid resisting apparatus.

More particularly the invention relates to improved constructionsfor acid containers,

acid towers, digesters, and retorts in which ordinary metals cannot be utilized because of chemical reactions with the substances contained therein. My improved apparatus is especially adapted for the manufacture of nitric acid, magnesium nitrate, manganese sulphate, and like compounds in carrying out the manufacture of the manganese dioxide such as set forth in patent numbered 1,325,-

129, issued December 16, 1919, and in the 1mproved process of Serial Number 101,432,

filed April 12th, 1926.

In the construction of retorts, acid towers, and apparatus of a similar character, it has heretofore been the practice to utilize ordinary metallic structures which are lined with materials such as brick. With linings of this character, due to porosity and the difference in expansion coeiiicients of the metallic shell, cracks and leaks develop in the lining through which chemicals leak to the shell, rapidly attacking and corroding the metal of the shell, causing leaks and rapid destruction of the apparatus.

An object of the present invention is to provide arrangement of acid resisting apparatus in which a metallic lining oering high resistance to ordinary mineral acids is provided. The lining is preferably made up in sections of cast iron with from approximately 12 to 15 percent silicia content. Metals known commercially as Cerros, Duriron or Tant iron are especially adapted for this purpose,

but it will be understood that any acid resisting metallic alloy which may be cast into suitable shapes may be utilized.

Another object of my invention is to provide simple and improved construction for digesters, retorts and acid resisting containers which are of durable construction and of relatively low cost to manufacture and maintain.

Further objects of the invention will appear as the description of the preferred embodiments of the invention proceeds and are 50 such as may be maintained by a utilization 1926. Serial No. 104,923.

of the various combinations and sub-combinations and principles hereinafter more fully set forth, and as defined by the terms of the appended claims.

Referring to the drawings,

Figure 1 is a sectional elevation of a digester or acid tower constructed in accordance with my invention.

Figure 2 is a sectional view taken along line A--A of Figure 1.

Figure 3 is a sectional view taken along line` B-,B of Figure 1.

Figure 4 is a detailed sectional view showing a preferred arrangement of securing dcv1ce.

Figure 5 is a sectional elevation through a retort designed to operate at high temperaturcs and constructed in accordance with my invention.

Referring to the drawings, an outer cylindrical metallic shell 1 is provided at the upper end of which a frusto conical metallic top section 2 is secured by riveting or in any other suitable manner. Fa'stened to top section 2 is a securing flange ring 3 to which the cover plate 4 of the digester or retort is secured. Formed in cover plate 4 a manhole section 5 to which the manhole cover 6 is pivotally secured, suitable hinge bolts 7 are provided for securing the manhole cover 6 in closed position. Secured in the cover plate 4 is a vapor outlet connection 8. The parts 4, 5, 6 and 8 are constructed of acid resisting metal such for example as Gorros, Duriron or Tant iron or of cast iron with a silicia content of from 12 to 15 percent.

Secured to the bottom of the shell 1, is a frusto conical bottom section 9, which at its lower end has fastened thereto a flange ring 10. Secured to 'the flange ring 10 by bolts or rivets is a bottom casting 11 of suitable acld resisting metal which is provided with the inlet land outlet connections 12 and 13. Supported by ribs 14 from the body of the casting 11 is a central ring 15 upon which an inner tubular member 17 constructed of acid resisting metal is supported. Secured to the top of the tubular member 17 by means of suitable bolts, and supported by acid resisting metal sections 18 is a deflecting member 19. The entire inner surface of the shell 1, the top section 2, and the bottom section 9 is lined with sections 20 of acid resisting metal which are cast in the proper shape to conform to and seat against the outer shell and to form overlapping joints 21 at their edges. Before the lining" sections 2 0 are placed into position, a coating of acid resisting cement of any well known and suitable type is applied to the surfaces to be lined and the overlapping portions of the sections 20. Sections 20 may be held in position entirely by the acid resisting cement, but special securing bolt members 22 are preferably provided. The particular type of acid prooi1 cements which are preferably used are those cements of the non-setting type i. c. those cements which harden with extreme slowness and do not expand under the influence of heat or acids. The acid proof cements of the setting type or the cements which set in a very hard mass may also be utilized for the purpose aforementioned but such cements possess the disadvantage in that they are readily broken by expansion where the joints or packings are rather large. Securing members 22 as shown in Figure 4, comprise an acid resisting cap 23 which is cast around and has imbedded therein a standard nut 24. Nut 24 is adapted to thread on the projecting inner end of a securing bolt 25 which has formed therein a duct 26. Bolts 25 extend through suitable holes formed in the outer metallic lshell and the lining sections 20, and the sections are held in position against the shell by means of standard nuts 27 and 28 of ordinary metal which are screwed tightly in position. Sufficient acid proof cement 1s referably applied to the lining and the slabs efore the nuts 27 and 28 are tightened, so that cement is forced outward through the joints as the nuts 27 and 28 are tightened. Caps 23 are then screwed tightly into position and acid proof cement, preferably of the non-setting type, is pumped through the duct 26 filling the space between the caps 23 and nuts 24 and 27, forming an acid proof shell around the securing holes formed in the sections 20. In this way the lining is tightly bolted into position and at the same time effective seals against leaks around the joints are provided. To support the tubular member 17, suitable acid resisting metallic braces 29 are provided.

For an understandin of i the apparatus shown in Figure 1, as a ig'ester or tower for the production of manganese sulphate, magnesium nitrate, and like products, reference may be had to copending application Serial Number 101,432 filed April 12th, 1926.

In the retort shown in Figure 5, the upper part is the same as set forth in Figure l, and like reference characters have been applied to similar parts. A lower conical section 30 secured to the shell is provided with a flange 31 to which a suitable casting 32 is secured by means .of bolts or threads. Casting 32 is provided with air and water inlet connections 33 and 34 and with a discharging outlet 35 to which a discharge valve 36 is secured. Parts 31 to 36 may be made of ordinary metal, when the retort is to be used for the production of manganese dioxide and magnesium sulphate or for similar rocesses as set forth in the above mentioned copending application, providing the retort ischarged -to a sufficient height so that the level or" the. reacting materials will be maintained above the lower edge of the acid )roof lining 20 throughout the reactions. eat is applied to thc outer surface of section 30 and with this construction, temperatures as high as 500 C. or more may be applied.

It will be obvious to those skilled in the art that my method of lining metallic containers with overlapping cast Sections of acid resisting metal held in position with acid proof. cement may be applied to the construction of containers and storage vats for acids and similar uses.

Accordingly, having described. preferred embodiments only of my invention, what -is desired to be secured by Letters Patent and claimed as new is: A

1. In acid resisting apparatus, an outer and inner section provided with openings therethrough and a securing means engaging the openings of the respective sections and extending through the said sections, each securing means including a bolt, a nut engaging one end of said bolt and a cap surrounding said nut, the inner section abutting against the said cap and means to seal the edges of said cap.l

2. Acid resisting apparatus comprising a double walled vessel including a plurality of inner and outermetallic sections held in nested relation by an acid proof cement and provided with openings disposed at intervals around said sections substantially centrally between the ends thereof and being so formed at their ends as to provide overlapping joints when in assembled position, and

the ends thereof and being so formed at their ends as to provide overlapping joints when in assembled position, acid proof cement interposed between adjacent inner and outer sections, and means adapted to be inserted in said openings and to secure the adjacent inner and outer sections together, acid resisting caps protecting the inner ends ot' said means,

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the said inner sections being composed of acid resisting material.

4. Acid resisting apparatus comprising a central portion including a plurality of outer and inner sections, the said sections having openings therethrough and being so formed at their ends as to provide overlapping joints when in* assembled position, and means eX- tending through the said openings and abutting against said sections for securing the respectivefadjacent sections together, acid resisting means to cover and seal said first named means, the said inner sections being composed of acid resisting material.

5. Aci'd resisting apparatus comprising a central portion including an outer and inner section provided with openings therethrough and means extending through the said openings for securing the respective sections to` gether, .said means comprising a threaded bolt, a nut, and a cap having its edges sealed surrounding said nut and abutting at its edges against said inner section, the said inner section being composed of acid resisting material.

6. Acid resisting apparatus comprising a central portion including an outer and inner section provided with openings therethrough, and fastening means extending through the said openings for securing the respective sections together, said means comprising .a threaded bolt provided with an opening V therethrough, a nutengaging one end of said bolt, and a cap surrounding said nut, the said inner section being composed of acid resisting material.

7. Acid resisting apparatus comprising a central and a bottom portion including a plurality of outer and inner sections, the saidl sections having openings therethrough and being so formed at their ends as to provide overlapping joints when in assembled position, means extending through the said openings -for securing the respective adjacent sections together, and a tubular member centrally disposed within the respective portions and supported by the said bottom portion, the said iniier sections'and tubular member being composed of acid resisting material.

8. Acid resisting apparatus comprising a top, central, and bottom portion including a plurality of outer and inner sections, the said sections having openings therethrough and bein so formed at their ends as to provide over apping joints when in assembled position, means extending through the said openings for securing the respective adjacent sec-v tions together, a tubular member extending into the central portion and supported by the bottom portion, 4and a cover provided with an inlet and an outlet secured to the said top portion, the said inner sections, tubular member and interior face of the top being composed of acid resisting material.

9. A container comprising an inner metal section of a composition having high acid resisting properties andan outer metal supporting section, said sections being arranged in nested relation and united by means including a nonsetting cement whereby relative expansion and contraction of said sections is permitted.

10. In acid'resisting apparatus, outer and inter metallic elements, each composed of a plurality of sections, the said sections being disposed with their sides in abutting relation and so formed at their ends as to provide overlapping joints projecting away from said abutting sides when in assembled condition, andan acid proof lcement interposed between the said sides and adapted to hold said sections together while permitting relative expansion and contraction of said sections, the inner section being composed of acid resisting material.

11. In acid 'resisting apparatus, an outer and an inner metallic section provided with openings therethrough, and a securing means including a member engaging the openings of the respective sections and extending therethrough, an acid resisting cap sealed with acid proof cement covering the exposed end of said member and abutting against said inner section, the inner section being composed of acid resisting material.

12. In acid resisting apparatus, a metallic outer section a metallic inner section composed of acid resisting material and arranged in nested relation to said outer section, and means to secure said sections together comprising a hollow threaded member extending through alined openings in said section, nuts threaded on said member and abutting against said sections, a cap threaded on said member and surrounding the nut abutting against said inner section and in spaced lrelation thereto, and means to supply acid proof cement to the space between said cap and nut from the exterior of said apparatus.

In testimony whereof I aflix my signature. l

GEORGE D. IKNIGHT. 

